Stem cell-derived brain repair for Parkinson’s disease: a review of strategies to improve engraftment

Abstract Induced pluripotent stem cell-derived dopaminergic progenitor transplantation has received conditional approval in Japan for Parkinson’s disease following the Kyoto Phase I/II trial. Early clinical studies demonstrate favourable safety and preliminary efficacy, but interpretation is limited by open-label designs. Preclinical evidence reveals variable graft survival and low differentiation efficiency, highlighting opportunities for optimisation. This review examines strategies to improve survival, differentiation, and functional integration of transplanted dopaminergic progenitors.